Polished stone
Quarry tile is a building construction material, usually 1⁄2 to 3⁄4 inch (13 to 19 mm) thick, made by the extrusion process from natural clay or shales. Quarry tile is manufactured from clay in a manner similar to bricks. It is shaped from clay, and fired at a high temperature, ~2,000 F°.
The most traditional size in the US is nominally 6 in × 6 in × 1⁄2 in thick. Other common sizes include 4 in × 8 in and 8 in × 8 in.
Traditional quarry tile was unglazed and either red or gray; however, modern "decorator" tiles come in a variety of tints and finishes. Industrial quarry tile is available with abrasive frit embedded in the surface to provide a non-slip finish in wet areas such as commercial kitchens and laboratories.
Quarry tile is extensively used for floors where a very durable material is required. It can be used either indoors or outdoors, although freeze-resistant grades of tile should be used outdoors in climates where freeze-thaw action occurs. Quarry tile is used less often as a wall finish and is occasionally used for countertops, although the wide grout joints can make cleaning of countertops difficult. Most commercial kitchens require a quarry tile to be used because of its slip resistant and non-porous properties.
For floors, quarry tile is usually set in a thick bed of cementitious mortar. For wall applications, it can be set in either a thick bed of cementitious mortar or a thin bed of mastic. For both floors and walls, the joints between tiles are usually grouted with cementitious grout. Grout joints are traditionally about 3⁄8 inch in width. Matching trim shapes such as coves, bases, shoes, and bullnoses are available to turn corners and terminate runs of the tile.
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